8th Grade Teaching Materials for NGSS

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Where’s the Evidence? (Day 3)

Today was the third day of our “Where’s the Evidence?” lab. Today’s reaction was called “making milk.” The students combined ice melt (CaCl2) with washing soda (Na2CO3). By dissolving the ice melt and washing soda in two separate beakers, students started with two clear liquids. Upon mixing them, the liquid suddenly turned bright white, similar to the color of milk.

It wasn’t magic; it was a chemical reaction. The sodium and calcium switched places, producing table salt (NaCl) and chalk (CaCO3). The chalk was what gave the mixture such a bright white color. A video of the reaction can be seen below.